BackgroundOsteogenesis imperfecta (OI), also known as brittle bone disease or Lobstein syndrome, is a congenital bone disorder characterized by brittle bones that are prone to fracture. People with OI are born with defective connective tissue in most cases secondary to a deficiency of type-I collagen, which represents approximately 75% of total collagen in the adult myocardium. The purpose of our study was to assess the prevalence of cardiomyopathy, electrocardiogram (ECG) abnormalities, and cardiovascular symptoms among patients with OI. MethodsWe studied 99 adults with OI from the national OI registry in Norway. Patients were divided into type I, III, and IV, and 52 control subjects. History and physical examination, ECG, and echocardiographic parameters of left ventricular (LV) and right ventricular (RV) systolic and diastolic function were obtained. ResultsECG abnormalities and cardiac symptoms were more common among patients with OI. RV and LV systolic peak velocity were significantly lower and diastolic mitral tricuspid valve wave and early diastolic tissue Doppler velocity ratio increased in the OI group compared with the control subjects; 5.7 ± 1.2 vs 6.3 ± 1.2 cm/s (P < 0.05) and 8 ± 1.8 vs 9.5 ± 1.4 cm/s (P < 0.05) and 9.8 ± 2.6 vs 7.4 ± 2.0 (P < 0.05) and 8.6 ± 3.3 vs 6.1 ± 1.4, respectively. In multivariate analysis OI was found to be an independent risk factor for RV systolic and diastolic dysfunction. ConclusionsCardiac symptoms and ECG changes are common among patients with OI. Our study findings suggest RV and LV systolic and diastolic function to be impaired in patients with OI compared with normal individuals. In multivariate analysis, however, OI was an independent predictor only of reduced RV systolic and diastolic function.